On Tue, Jan 06, 2015 at 11:09:16AM +0530, Pankaj Gupta wrote: > Networking under kvm works best if we allocate a per-vCPU RX and TX > queue in a virtual NIC. This requires a per-vCPU queue on the host side. > > It is now safe to increase the maximum number of queues. > Preceding patch: 'net: allow large number of rx queues' > made sure this won't cause failures due to high order memory > allocations. Increase it to 256: this is the max number of vCPUs > KVM supports. > > Size of tun_struct changes from 8512 to 10496 after this patch. This keeps > pages allocated for tun_struct before and after the patch to 3. > > Signed-off-by: Pankaj Gupta <[email protected]> > Reviewed-by: David Gibson <[email protected]> > --- > drivers/net/tun.c | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) > > diff --git a/drivers/net/tun.c b/drivers/net/tun.c > index e3fa65a..a19dc5f8 100644 > --- a/drivers/net/tun.c > +++ b/drivers/net/tun.c > @@ -113,10 +113,11 @@ struct tap_filter { > unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN]; > }; > > -/* DEFAULT_MAX_NUM_RSS_QUEUES were chosen to let the rx/tx queues allocated > for > - * the netdevice to be fit in one page. So we can make sure the success of > - * memory allocation. TODO: increase the limit. */ > -#define MAX_TAP_QUEUES DEFAULT_MAX_NUM_RSS_QUEUES > +/* MAX_TAP_QUEUES 256 is chosen to allow rx/tx queues to be equal > + * to max number of vCPUS in guest.
VCPUs I think. > Also, we are making sure here > + * queue memory allocation do not fail. What does this mean? How are we making sure? I would drop this phrase really. > + */ > +#define MAX_TAP_QUEUES 256 > #define MAX_TAP_FLOWS 4096 > > #define TUN_FLOW_EXPIRE (3 * HZ) > -- > 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
